In __cvdso_clock_getres_time32(), when clock_getres_fallback()
fails, it's not required to update the struct timespec res.
Signed-off-by: Chiawei Wang <chiaweiwang@google.com>
Reviewed-by: Mark Salyzyn <salyzyn@google.com>
Bug: 159086668
Bug: 154668398
Test: run cts -m CtsBionicTestCases -t time#clock_getres_unknown
Change-Id: Ibb7279d4520658d5c8be76e721249d3c62267d9f
The vDSO library should only include the necessary headers required for
a userspace library (UAPI and a minimal set of kernel headers). To make
this possible it is necessary to isolate from the kernel headers the
common parts that are strictly necessary to build the library.
Refactor the unified vdso code to use the common headers.
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200320145351.32292-26-vincenzo.frascino@arm.com
(cherry picked from commit 8c59ab839f526437831ff6d1405c9a6d93f475eb)
Signed-off-by: Mark Salyzyn <salyzyn@google.com>
Bug: 154668398
Change-Id: Ic0890fed51d4e570e50da6c553bdcbce412d0683
If the architecture knows at compile time that there is no VDSO capable
clocksource supported it makes sense to optimize the guts of the high
resolution parts of the VDSO out at build time. Add a helper function to
check whether the VDSO should be high resolution capable and provide a stub
which can be overridden by an architecture.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Link: https://lkml.kernel.org/r/20200207124402.530143168@linutronix.de
(cherry picked from commit 1dff4156d1f63b525c54aea7f097a657cbbbf837)
Signed-off-by: Mark Salyzyn <salyzyn@google.com>
Bug: 154668398
Change-Id: Ib024363345b8d75ffc78b3e5598a5720926f9358
Only perform READ_ONCE(vd[CS_HRES_COARSE].hrtimer_res) for
HRES and RAW clocks.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/7ac2f0d21652f95e2bbdfa6bd514ae6c7caf53ab.1579196675.git.christophe.leroy@c-s.fr
(cherry picked from commit 49a101d7169c7729c7bab6b2f896faae34bd6c3d)
Signed-off-by: Mark Salyzyn <salyzyn@google.com>
Bug: 154668398
Change-Id: I0441a793d4703755e8026f23c07e5c1f12544319
VDSO_HRES and VDSO_RAW clocks are handled the same way.
Avoid the code duplication.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Link: https://lore.kernel.org/r/fdf1a968a8f7edd61456f1689ac44082ebb19c15.1577111367.git.christophe.leroy@c-s.fr
(cherry picked from commit cdb7c5a9c897ab2e5c56df647dd84c84e150e925)
Signed-off-by: Mark Salyzyn <salyzyn@google.com>
Bug: 154668398
Change-Id: I765c9ddf53427d970e8b186cf4d37623c9218f25
do_coarse() is similar to do_hres() except that it never fails.
Change its type to int instead of void and let it always return success (0)
to simplify the call site.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/21e8afa38c02ca8672c2690307383507fe63b454.1577111367.git.christophe.leroy@c-s.fr
(cherry picked from commit 8463cf80529d0fd80b84cd5ab8b9b952b01c7eb9)
Signed-off-by: Mark Salyzyn <salyzyn@google.com>
Bug: 154668398
Change-Id: Ia57b47a7ed90e102fa3323311d998b2f77989bda
Since all the architectures that support the generic vDSO library have
been converted to support the 32 bit fallbacks it is not required
anymore to check the return value of __cvdso_clock_get*time32_common()
before updating the old_timespec fields.
Remove the related checks from the generic vdso library.
References: c60a32ea4f45 ("lib/vdso/32: Provide legacy syscall fallbacks")
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20190830135902.20861-6-vincenzo.frascino@arm.com
(cherry picked from commit a279235ddbe975670afe2267162028ec0a312293)
Signed-off-by: Mark Salyzyn <salyzyn@google.com>
Bug: 154668398
Change-Id: I31637fcdac30262c1837b098345a2c057794ea17
clock_gettime32 and clock_getres_time32 should be compiled only with a
32 bit vdso library.
Exclude these symbols when BUILD_VDSO32 is not defined.
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Link: https://lore.kernel.org/r/20190830135902.20861-3-vincenzo.frascino@arm.com
(cherry picked from commit bf279849ad59538a1518c667c0795ec1fe9dbd66)
Signed-off-by: Mark Salyzyn <salyzyn@google.com>
Bug: 154668398
Change-Id: I4d3563ab9aaa839da2b314b3a1eb96d68f78e2c6
Fix the following sparse warning in the generic vDSO library:
linux/lib/vdso/gettimeofday.c:224:5: warning: symbol
'__cvdso_clock_getres' was not declared. Should it be static?
Make it static and also mark it __maybe_unsed.
Fixes: 502a590a170b ("lib/vdso: Move fallback invocation to the callers")
Reported-by: Marc Gonzalez <marc.w.gonzalez@free.fr>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20191128111719.8282-1-vincenzo.frascino@arm.com
(cherry picked from commit ffd08731b2d632459428612431060cf902324a8d)
Signed-off-by: Mark Salyzyn <salyzyn@google.com>
Bug: 154668398
Change-Id: I9842a0811350fc325315b25ba3f41e4b626a97c0
A recent commit removed the NULL pointer check from the clock_getres()
implementation causing a test case to fault.
POSIX requires an explicit NULL pointer check for clock_getres() aside of
the validity check of the clock_id argument for obscure reasons.
Add it back for both 32bit and 64bit.
Note, this is only a partial revert of the offending commit which does not
bring back the broken fallback invocation in the the 32bit compat
implementations of clock_getres() and clock_gettime().
Fixes: a9446a906f52 ("lib/vdso/32: Remove inconsistent NULL pointer checks")
Reported-by: Andreas Schwab <schwab@linux-m68k.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/alpine.DEB.2.21.1910211202260.1904@nanos.tec.linutronix.de
(cherry picked from commit 1638b8f096ca165965189b9626564c933c79fe63)
Signed-off-by: Mark Salyzyn <salyzyn@google.com>
Bug: 154668398
Change-Id: I3a157d989ec54577781742d69380261bc4279676
To address the regression which causes seccomp to deny applications the
access to clock_gettime64() and clock_getres64() syscalls because they
are not enabled in the existing filters.
That trips over the fact that 32bit VDSOs use the new clock_gettime64() and
clock_getres64() syscalls in the fallback path.
Add a conditional to invoke the 32bit legacy fallback syscalls instead of
the new 64bit variants. The conditional can go away once all architectures
are converted.
Fixes: 00b26474c2f1 ("lib/vdso: Provide generic VDSO implementation")
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Sean Christopherson <sean.j.christopherson@intel.com>
Reviewed-by: Sean Christopherson <sean.j.christopherson@intel.com>
Link: https://lkml.kernel.org/r/alpine.DEB.2.21.1907301134470.1738@nanos.tec.linutronix.de
(cherry picked from commit c60a32ea4f459f99b98d383cad3b1ac7cfb3f4be)
Signed-off-by: Mark Salyzyn <salyzyn@google.com>
Bug: 154668398
Change-Id: I8aea8f1282566f6b3f02dd021206af02469f6944
To allow syscall fallbacks using the legacy 32bit syscall for 32bit VDSO
builds, move the fallback invocation out into the callers.
Split the common code out of __cvdso_clock_gettime/getres() and invoke the
syscall fallback in the 64bit and 32bit variants.
Preparatory work for using legacy syscalls in 32bit VDSO. No functional
change.
Fixes: 00b26474c2f1 ("lib/vdso: Provide generic VDSO implementation")
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Link: https://lkml.kernel.org/r/20190728131648.695579736@linutronix.de
(cherry picked from commit 502a590a170b3b3d0ad998ee0b639ac0b3db1dfa)
Signed-off-by: Mark Salyzyn <salyzyn@google.com>
Bug: 154668398
Change-Id: I1361d4ccfd99292c3d346325be2068b93cbcadca
The 32bit variants of vdso_clock_gettime()/getres() have a NULL pointer
check for the timespec pointer. That's inconsistent vs. 64bit.
But the vdso implementation will never be consistent versus the syscall
because the only case which it can handle is NULL. Any other invalid
pointer will cause a segfault. So special casing NULL is not really useful.
Remove it along with the superflouos syscall fallback invocation as that
will return -EFAULT anyway. That also gets rid of the dubious typecast
which only works because the pointer is NULL.
Fixes: 00b26474c2f1 ("lib/vdso: Provide generic VDSO implementation")
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Link: https://lkml.kernel.org/r/20190728131648.587523358@linutronix.de
(cherry picked from commit a9446a906f52292c52ecbd5be78eaa4d8395756c)
Signed-off-by: Mark Salyzyn <salyzyn@google.com>
Bug: 154668398
Change-Id: I2d4563f336f8cc6b44f1b74f92467c4c6a579710
The x86 vdso implementation on which the generic vdso library is based on
has subtle (unfortunately undocumented) twists:
1) The code assumes that the clocksource mask is U64_MAX which means that
no bits are masked. Which is true for any valid x86 VDSO clocksource.
Stupidly it still did the mask operation for no reason and at the wrong
place right after reading the clocksource.
2) It contains a sanity check to catch the case where slightly
unsynchronized TSC values can be observed which would cause the delta
calculation to make a huge jump. It therefore checks whether the
current TSC value is larger than the value on which the current
conversion is based on. If it's not larger the base value is used to
prevent time jumps.
reason it is also completely wrong for clocksources with a smaller mask
which can legitimately wrap around during a conversion period. The core
timekeeping code does it correct by applying the mask after the delta
calculation:
(now - base) & mask
around during a conversion period because there the now > base check is
just wrong and causes stale time stamps and time going backwards issues.
Unbreak it by:
1) Removing the mask operation from the clocksource read which makes the
fallback detection work for all clocksources
2) Replacing the conditional delta calculation with a overrideable inline
function.
results in a significant performance hit for the x86 VSDO. The timekeeping
core code must have the non optimized version as it has to operate
correctly with clocksources which have smaller masks as well to handle the
case where TSC is discarded as timekeeper clocksource and replaced by HPET
or pmtimer. For the VDSO there is no replacement clocksource. If TSC is
unusable the syscall is enforced which does the right thing.
To accommodate to the needs of various architectures provide an
override-able inline function which defaults to the regular delta
calculation with masking:
(now - base) & mask
Override it for x86 with the non-masking and checking version.
This unbreaks the ARM64 syscall fallback operation, allows to use
clocksources with arbitrary width and preserves the performance
optimization for x86.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: linux-arch@vger.kernel.org
Cc: LAK <linux-arm-kernel@lists.infradead.org>
Cc: linux-mips@vger.kernel.org
Cc: linux-kselftest@vger.kernel.org
Cc: catalin.marinas@arm.com
Cc: Will Deacon <will.deacon@arm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: linux@armlinux.org.uk
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: paul.burton@mips.com
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: salyzyn@android.com
Cc: pcc@google.com
Cc: shuah@kernel.org
Cc: 0x7f454c46@gmail.com
Cc: linux@rasmusvillemoes.dk
Cc: huw@codeweavers.com
Cc: sthotton@marvell.com
Cc: andre.przywara@arm.com
Cc: Andy Lutomirski <luto@kernel.org>
Link: https://lkml.kernel.org/r/alpine.DEB.2.21.1906261159230.32342@nanos.tec.linutronix.de
(cherry picked from commit 9d90b93bf325e015bbae31b83f16da5e4e17effa)
Signed-off-by: Mark Salyzyn <salyzyn@google.com>
Bug: 154668398
Change-Id: I190d30a966ab65330a230ce84f71eaa70b80792b
arm64 was the last architecture using CROSS_COMPILE_COMPAT_VDSO config
option. With this patch series the dependency in the architecture has
been removed.
Remove CROSS_COMPILE_COMPAT_VDSO from the Unified vDSO library code.
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
(cherry picked from commit 50a2610adec9d796b25e262734edb56ef324ce15)
Signed-off-by: Mark Salyzyn <salyzyn@google.com>
Bug: 154668398
Change-Id: I5cd788546e59e71b76af68cf845e8dd45a6bdc61
Some 64 bit architectures have support for 32 bit applications that
require a separate version of the vDSOs.
Add support to the generic code for compat fallback functions.
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Shijith Thotton <sthotton@marvell.com>
Tested-by: Andre Przywara <andre.przywara@arm.com>
Cc: linux-arch@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-mips@vger.kernel.org
Cc: linux-kselftest@vger.kernel.org
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Mark Salyzyn <salyzyn@android.com>
Cc: Peter Collingbourne <pcc@google.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Dmitry Safonov <0x7f454c46@gmail.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Huw Davies <huw@codeweavers.com>
Link: https://lkml.kernel.org/r/20190621095252.32307-10-vincenzo.frascino@arm.com
(cherry picked from commit 629fdf77ac4584b73bf3a7a07f5fc5ab0d27afdc)
Signed-off-by: Mark Salyzyn <salyzyn@google.com>
Bug: 154668398
Change-Id: I31097f39d6950966b6ae3689d520fb87ef77416e
In the last few years the kernel gained quite some architecture specific
vdso implementations which contain very similar code.
Introduce a generic VDSO implementation of gettimeofday() which will be
shareable between architectures once they are converted over.
The implementation is based on the current x86 VDSO code.
[ tglx: Massaged changelog and made the kernel doc tabular ]
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Shijith Thotton <sthotton@marvell.com>
Tested-by: Andre Przywara <andre.przywara@arm.com>
Cc: linux-arch@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-mips@vger.kernel.org
Cc: linux-kselftest@vger.kernel.org
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Mark Salyzyn <salyzyn@android.com>
Cc: Peter Collingbourne <pcc@google.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Dmitry Safonov <0x7f454c46@gmail.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Huw Davies <huw@codeweavers.com>
Link: https://lkml.kernel.org/r/20190621095252.32307-3-vincenzo.frascino@arm.com
(cherry picked from commit 00b26474c2f1613d7ab894c525f775c67c8a9e8f)
Signed-off-by: Mark Salyzyn <salyzyn@google.com>
Bug: 154668398
Change-Id: I6d3031546e60ea5a883ea34198999a3fd0f34351
